Indian Space agency ISRO has commenced a 22-hour countdown for its first launch mission of 2026, the 'PSLV-C62/EOS-N1'. The PSLV rocket, in its 64th&nbsp;flight is expected to liftoff from the first launchpad of Satish Dhawan Space Centre, Sriharikota at 10:18am IST, Monday, (12th&nbsp;Jan).&nbsp;&nbsp;The&nbsp;countdown&nbsp;is a well-planned technical process during which the final health checks of various systems of the rocket and satellite are carried out, and the liquid-fuel stages of the rocket are tanked up.&nbsp;&nbsp;This flight marks PSLV's return to flight after a rare setback during the previous launch in May 2025. In May 2025, the PSLV rocket suffered a mid-flight failure. The PSLV's third stage malfunction led to the loss of the rocket and the EOS-09 radar imaging satellite. The May 2025 flight marked the third major failure of the PSLV in its 63 flights across 32 years.&nbsp;&nbsp;The primary satellite of this mission is the 'EOS-N1' or 'Anvesha', an Earth Observation satellite built by India's Defence Research Development Organization(DRDO). This satellite is to be placed 511kms above the Earth. 'EOS-N1' is Hyperspectral imaging satellite, which means it can see much more than the human eye or a conventional optical-imaging satellite. As the surface of the Earth gets illuminated, different materials(soil, water, metal, vegetation) reflect light, across various wavelengths. A hyperspectral sensor can capture these reflections and identify how an object appears and what it is made of.&nbsp;&nbsp;This technology has immense civilian and strategic applications, as it can scan the Earth based on unique light signatures. In simple terms, it can identify different materials based on their unique fingerprint(spectral signature).Water quality, soil composition, crop health, are among the environmental aspects that can be studied using this technology. Military targets under camouflage can also be detected, based on the reflection from the material. It can also be used for supporting mining and exploration.In addition to 'EOS-N1', there will be 15 co-passenger satellites aboard the PSLV. Seven satellites are from India, while two of them are from Europe, five of them are from Brazil, and one from Nepal. Many of these satellites are from academia or startups, and are meant to demonstrate unique experiments in space.&nbsp;

This flight marks PSLV's return to flight after a rare setback during the previous launch in May 2025. In May 2025, the PSLV rocket suffered a mid-flight failure.

Indian Space agency ISRO has commenced a 22-hour countdown for its first launch mission of 2026, the 'PSLV-C62/EOS-N1'. The PSLV rocket, in its 64th flight is expected to liftoff from the first launchpad of Satish Dhawan Space Centre, Sriharikota at 10:18am IST, Monday, (12th Jan). The countdown is a well-planned technical process during which the final health checks of various systems of the rocket and satellite are carried out, and the liquid-fuel stages of the rocket are tanked up. This flight marks PSLV's return to flight after a rare setback during the previous launch in May 2025. In May 2025, the PSLV rocket suffered a mid-flight failure. The PSLV's third stage malfunction led to the loss of the rocket and the EOS-09 radar imaging satellite. The May 2025 flight marked the third major failure of the PSLV in its 63 flights across 32 years. The primary satellite of this mission is the 'EOS-N1' or 'Anvesha', an Earth Observation satellite built by India's Defence Research Development Organization(DRDO). This satellite is to be placed 511kms above the Earth. 'EOS-N1' is Hyperspectral imaging satellite, which means it can see much more than the human eye or a conventional optical-imaging satellite. As the surface of the Earth gets illuminated, different materials(soil, water, metal, vegetation) reflect light, across various wavelengths. A hyperspectral sensor can capture these reflections and identify how an object appears and what it is made of. This technology has immense civilian and strategic applications, as it can scan the Earth based on unique light signatures. In simple terms, it can identify different materials based on their unique fingerprint(spectral signature). Water quality, soil composition, crop health, are among the environmental aspects that can be studied using this technology. Military targets under camouflage can also be detected, based on the reflection from the material. It can also be used for supporting mining and exploration. In addition to 'EOS-N1', there will be 15 co-passenger satellites aboard the PSLV. Seven satellites are from India, while two of them are from Europe, five of them are from Brazil, and one from Nepal. Many of these satellites are from academia or startups, and are meant to demonstrate unique experiments in space.

This flight marks PSLV's return to flight after a rare setback during the previous launch in May 2025. In May 2025, the PSLV rocket suffered a mid-flight failure.

ISRO's PSLV to launch 16 satellites; 22hr countdown starts

Indian space agency ISRO's workhorse PSLV rocket is back on the launchpad for a mission on Monday, (Jan 12). Dubbed 'PSLV-C62', this launch marks PSLV's return to flight after a rare failure in May 2025. Back then, the PSLV's third stage malfunction led to the loss of the rocket and the EOS-09 radar imaging satellite mid-flight. The May 2025 flight marked the third major failure of the PSLV in its 63 flights across 32 years.In what is its first mission of 2026, ISRO has announced that the 'PSLV-C62' vehicle is expected to liftoff from the First launchpad at Satish Dhawan Space Centre, Sriharikota, at 10:17 am. While the PSLV will be carrying multiple satellites to Earth orbit, its primary satellite will be the EOS-N1 or Anvesha, a hyperspectral Earth-imaging satellite built by DRDO.In addition to the primary satellite, there will be multiple small satellites and experiments that are from India and abroad.<h2>'PSLV C-61' failure in May 2025</h2>On Sunday, 18th May, barely eight minutes after liftoff, ISRO halted its live broadcast of the PSLV-C61/EOS-09 mission. "Up to the second stage, performance was normal. Third stage ignited, but we made an observation regarding its functioning. Mission could not be accomplished. We are studying the data," said ISRO Chief Dr V. Narayanan, following the mishap.Addressing journalists at the spaceport, the ISRO Chief had elaborated on the observations. "The third stage of the PSLV uses a solid-fuel motor system. There was a fall in the chamber pressure in the motor case. We are studying the entire performance," the ISRO Chief had said in May.<h2>PSLV-C61 Failure Analysis Committee report yet to be made public</h2>As a taxpayer-funded civilian space agency founded with the ideals of serving the people of India, ISRO has made public the Failure Analysis Committee(FAC) reports. These FAC reports are typically readied by in-house experts within a few months of the failure.However, the FAC report related to the May 2025 PSLV-C61 has not been publicly released so far. &nbsp;Likewise, the FAC report pertaining to the failure of the NVS-02 satellite in January 2025 remains unreleased to the public. This is widely seen as a departure from the "ISRO culture". However, both these FAC reports are learnt to have been tabled before the Government of India.Given ISRO's role in launching foreign satellites belonging to governments and private firms, FAC reports being made public are crucial for maintaining transparency and re-establishing confidence.

In what is its first mission of 2026, ISRO has announced that the 'PSLV-C62' vehicle is expected to liftoff from the First launchpad at Satish Dhawan Space Centre, Sriharikota, at 10:17 am on Jan 12. 

Indian space agency ISRO's workhorse PSLV rocket is back on the launchpad for a mission on Monday, (Jan 12). Dubbed 'PSLV-C62', this launch marks PSLV's return to flight after a rare failure in May 2025. Back then, the PSLV's third stage malfunction led to the loss of the rocket and the EOS-09 radar imaging satellite mid-flight. The May 2025 flight marked the third major failure of the PSLV in its 63 flights across 32 years. In what is its first mission of 2026, ISRO has announced that the 'PSLV-C62' vehicle is expected to liftoff from the First launchpad at Satish Dhawan Space Centre, Sriharikota, at 10:17 am. While the PSLV will be carrying multiple satellites to Earth orbit, its primary satellite will be the EOS-N1 or Anvesha, a hyperspectral Earth-imaging satellite built by DRDO. In addition to the primary satellite, there will be multiple small satellites and experiments that are from India and abroad. 'PSLV C-61' failure in May 2025 On Sunday, 18th May, barely eight minutes after liftoff, ISRO halted its live broadcast of the PSLV-C61/EOS-09 mission. "Up to the second stage, performance was normal. Third stage ignited, but we made an observation regarding its functioning. Mission could not be accomplished. We are studying the data," said ISRO Chief Dr V. Narayanan, following the mishap. Addressing journalists at the spaceport, the ISRO Chief had elaborated on the observations. "The third stage of the PSLV uses a solid-fuel motor system. There was a fall in the chamber pressure in the motor case. We are studying the entire performance," the ISRO Chief had said in May. PSLV-C61 Failure Analysis Committee report yet to be made public As a taxpayer-funded civilian space agency founded with the ideals of serving the people of India, ISRO has made public the Failure Analysis Committee(FAC) reports. These FAC reports are typically readied by in-house experts within a few months of the failure. However, the FAC report related to the May 2025 PSLV-C61 has not been publicly released so far. Likewise, the FAC report pertaining to the failure of the NVS-02 satellite in January 2025 remains unreleased to the public. This is widely seen as a departure from the "ISRO culture". However, both these FAC reports are learnt to have been tabled before the Government of India. Given ISRO's role in launching foreign satellites belonging to governments and private firms, FAC reports being made public are crucial for maintaining transparency and re-establishing confidence.

In what is its first mission of 2026, ISRO has announced that the 'PSLV-C62' vehicle is expected to liftoff from the First launchpad at Satish Dhawan Space Centre, Sriharikota, at 10:17 am on Jan 12.&nbsp;

After rare May 2025 failure, ISRO's PSLV to fly on Jan 12th

ISRO’s LVM3 M6 rocket successfully launches the BlueBird Block-2 satellite into orbit for U.S.-based AST SpaceMobile, advancing global space-based connectivity.


ISRO: LVM3-M6 lifts off with its heaviest payload ever

ISRO’s LVM3 M6 rocket successfully launches the BlueBird Block-2 satellite into orbit for U.S.-based AST SpaceMobile, advancing global space-based connectivity.

Rocket Expert India Launches Heaviest Satellite as Other Countries Flop

LVM3-M6 lifts off, ISRO chief hails the successful launch from Sriharikota

ISRO chief: LVM3 can carry up to 9,200 kg to low Earth orbit

India launches heaviest satellite ever on LVM3 rocket

Think about the last time you felt truly proud to be Indian. Maybe it was during a cricket match, or when you saw our flag at the Olympics. But this year, 2025, has given us so many more reasons to feel that pride—and it all happened thousands of kilometers above our heads, in the vastness of space.&nbsp;Just this morning, December 24, 2025, while most of us were preparing for the day, ISRO launched something absolutely massive into space. The BlueBird 6 satellite weighs 6,500 kilograms—imagine lifting three full-sized cars and throwing them into orbit! What makes this even more incredible is what it can do. This satellite can beam internet directly to your smartphone, even if you are trekking in Ladakh or traveling through the deserts of Rajasthan where there are no mobile towers. High-speed 4G and 5G, available anywhere in India. That is not science fiction anymore—it is our reality now.&nbsp;But let me take you back to where this amazing year really began. On January 16, 2025, ISRO did something that only three other countries had ever managed. They launched two small spacecraft on December 30, 2024, and made them "dock" in space—basically, they made two machines traveling at 28,000 kilometers per hour connect perfectly, like threading a needle while riding a bullet train. Why does this matter? Because without this technology, we cannot build our own space station. And yes, India is planning its own space station (Bharatiya Antariksh Station) by 2047. The SpaDeX mission did not stop there. By April 21, one satellite was even transferring power to another in space. We are not just reaching space anymore; we are learning how to live and work there.&nbsp;Here is something that might sound strange: ISRO sent cowpea seeds to space in the CROPS-1 experiment. Within 90 minutes of adding water, they started germinating. By day five, tiny green leaves appeared. Why would anyone grow plants in space? Because if we are going to Mars or building a Moon base, we need to know if we can grow our own food. Now we know—Indian crops can survive in space. This year, we also looked closely at our own planet. ISRO satellites helped farmers by forecasting that India would produce 122.724 million tonnes of wheat by March 31, 2025, helping the government plan for food security.&nbsp;On January 29, 2025, ISRO reached a historic milestone by completing its 100th launch from Sriharikota. One hundred times our rockets have pierced through the clouds, carrying dreams and technology into orbit. While some missions faced technical challenges, like the satellite valve issues after the January 29 launch, every mission taught us something valuable. On March 4, 2025, our POEM-4 platform completed 1,000 orbits, carrying a record 24 different experiments, including space robotics and AI.&nbsp;For those of you interested in engineering, March 5, 2025, was a big day. ISRO unveiled two microprocessors—VIKRAM3201 and KALPANA3201—designed and made entirely in India. These are the computer "brains" that will control our future rockets. Later, on March 27, we finished a 1,000-hour test of an "Electric Engine" that is six times more efficient than traditional rocket fuel. This means future satellites can stay in space much longer.The most emotional moment came on June 25, 2025, when Shubhanshu Shukla became the first Indian to visit the International Space Station (ISS). For 18 days, he lived among the stars, conducting experiments on how muscles and plants behave in zero gravity. On June 28, he spoke to our Prime Minister from space, and on July 3, he talked to school students, showing them that the kid sitting in their classroom today could one day float in space too.&nbsp;Speaking of Gaganyaan—India’s dream of sending our own astronauts to space—the preparations are intense. A crew capsule uses 10 different parachutes to land safely. ISRO tested them by dropping a simulated module from a helicopter on August 24, 2025. Then, on December 18-19, just last week, they successfully tested the "drogue" parachutes using rocket sleds in Chandigarh. These tests are about one thing: bringing our astronauts back home safely to their families.&nbsp;ISRO also proved that space is now open for everyone. On August 8, they tested a rocket motor for Skyroot Aerospace, a private startup. On September 10, they signed an agreement with HAL to produce rockets commercially. Even more exciting, from April to December, over 700 students from Northeast India visited ISRO centers to see where history is made. They met scientists who studied in regular schools and faced the same board exams you do.&nbsp;Other massive highlights include the July 30 launch of NISAR, a joint mission with NASA to scan Earth for earthquakes and disasters, and the July 31 inauguration of the HOPE mission in Ladakh, where scientists are living in extreme cold to prepare for life on Mars. On November 2, ISRO launched CMS-03, the heaviest satellite we ever sent to its high orbit from Indian soil, using a cryogenic engine that was restarted while in space—a feat only a few nations can do.&nbsp;As I write this, looking at today's successful BlueBird 6 launch, it is clear we are living through something extraordinary. Every time an Indian rocket lifts off, it carries our ambitions and our refusal to be left behind. Somewhere in India right now, a teenager is looking up at the night sky and dreaming. Thanks to ISRO’s remarkable 2025, that dream does not seem impossible anymore. It seems inevitable. Could the next great scientist or astronaut be you?&nbsp;KEY DATES TO REMEMBER:Jan 6: Aditya-L1 Sun mission data releasedJan 16: Successful Space Docking (The Space Handshake)Jan 29: 100th Launch from SriharikotaMar 5: First Made-in-India space microprocessors unveiledJun 25: First Indian visits the International Space StationJul 30: NISAR (India-NASA) satellite launchAug 24: Gaganyaan major parachute air drop testDec 18-19: Final safety tests for Gaganyaan parachutesDec 24: BlueBird 6 launch (Heaviest commercial satellite)

Every time an Indian rocket lifts off, it carries our ambitions and our refusal to be left behind. Somewhere in India right now, a teenager is looking up at the night sky and dreaming. Thanks to ISRO’s remarkable 2025, that dream does not seem impossible anymore. 

Think about the last time you felt truly proud to be Indian. Maybe it was during a cricket match, or when you saw our flag at the Olympics. But this year, 2025, has given us so many more reasons to feel that pride—and it all happened thousands of kilometers above our heads, in the vastness of space. Just this morning, December 24, 2025, while most of us were preparing for the day, ISRO launched something absolutely massive into space. The BlueBird 6 satellite weighs 6,500 kilograms—imagine lifting three full-sized cars and throwing them into orbit! What makes this even more incredible is what it can do. This satellite can beam internet directly to your smartphone, even if you are trekking in Ladakh or traveling through the deserts of Rajasthan where there are no mobile towers. High-speed 4G and 5G, available anywhere in India. That is not science fiction anymore—it is our reality now. But let me take you back to where this amazing year really began. On January 16, 2025, ISRO did something that only three other countries had ever managed. They launched two small spacecraft on December 30, 2024, and made them "dock" in space—basically, they made two machines traveling at 28,000 kilometers per hour connect perfectly, like threading a needle while riding a bullet train. Why does this matter? Because without this technology, we cannot build our own space station. And yes, India is planning its own space station (Bharatiya Antariksh Station) by 2047. The SpaDeX mission did not stop there. By April 21, one satellite was even transferring power to another in space. We are not just reaching space anymore; we are learning how to live and work there. Here is something that might sound strange: ISRO sent cowpea seeds to space in the CROPS-1 experiment. Within 90 minutes of adding water, they started germinating. By day five, tiny green leaves appeared. Why would anyone grow plants in space? Because if we are going to Mars or building a Moon base, we need to know if we can grow our own food. Now we know—Indian crops can survive in space. This year, we also looked closely at our own planet. ISRO satellites helped farmers by forecasting that India would produce 122.724 million tonnes of wheat by March 31, 2025, helping the government plan for food security. On January 29, 2025, ISRO reached a historic milestone by completing its 100th launch from Sriharikota. One hundred times our rockets have pierced through the clouds, carrying dreams and technology into orbit. While some missions faced technical challenges, like the satellite valve issues after the January 29 launch, every mission taught us something valuable. On March 4, 2025, our POEM-4 platform completed 1,000 orbits, carrying a record 24 different experiments, including space robotics and AI. For those of you interested in engineering, March 5, 2025, was a big day. ISRO unveiled two microprocessors—VIKRAM3201 and KALPANA3201—designed and made entirely in India. These are the computer "brains" that will control our future rockets. Later, on March 27, we finished a 1,000-hour test of an "Electric Engine" that is six times more efficient than traditional rocket fuel. This means future satellites can stay in space much longer. The most emotional moment came on June 25, 2025, when Shubhanshu Shukla became the first Indian to visit the International Space Station (ISS). For 18 days, he lived among the stars, conducting experiments on how muscles and plants behave in zero gravity. On June 28, he spoke to our Prime Minister from space, and on July 3, he talked to school students, showing them that the kid sitting in their classroom today could one day float in space too. Speaking of Gaganyaan—India’s dream of sending our own astronauts to space—the preparations are intense. A crew capsule uses 10 different parachutes to land safely. ISRO tested them by dropping a simulated module from a helicopter on August 24, 2025. Then, on December 18-19, just last week, they successfully tested the "drogue" parachutes using rocket sleds in Chandigarh. These tests are about one thing: bringing our astronauts back home safely to their families. ISRO also proved that space is now open for everyone. On August 8, they tested a rocket motor for Skyroot Aerospace, a private startup. On September 10, they signed an agreement with HAL to produce rockets commercially. Even more exciting, from April to December, over 700 students from Northeast India visited ISRO centers to see where history is made. They met scientists who studied in regular schools and faced the same board exams you do. Other massive highlights include the July 30 launch of NISAR, a joint mission with NASA to scan Earth for earthquakes and disasters, and the July 31 inauguration of the HOPE mission in Ladakh, where scientists are living in extreme cold to prepare for life on Mars. On November 2, ISRO launched CMS-03, the heaviest satellite we ever sent to its high orbit from Indian soil, using a cryogenic engine that was restarted while in space—a feat only a few nations can do. As I write this, looking at today's successful BlueBird 6 launch, it is clear we are living through something extraordinary. Every time an Indian rocket lifts off, it carries our ambitions and our refusal to be left behind. Somewhere in India right now, a teenager is looking up at the night sky and dreaming. Thanks to ISRO’s remarkable 2025, that dream does not seem impossible anymore. It seems inevitable. Could the next great scientist or astronaut be you? KEY DATES TO REMEMBER: Jan 6: Aditya-L1 Sun mission data released Jan 16: Successful Space Docking (The Space Handshake) Jan 29: 100th Launch from Sriharikota Mar 5: First Made-in-India space microprocessors unveiled Jun 25: First Indian visits the International Space Station Jul 30: NISAR (India-NASA) satellite launch Aug 24: Gaganyaan major parachute air drop test Dec 18-19: Final safety tests for Gaganyaan parachutes Dec 24: BlueBird 6 launch (Heaviest commercial satellite)

Every time an Indian rocket lifts off, it carries our ambitions and our refusal to be left behind. Somewhere in India right now, a teenager is looking up at the night sky and dreaming. Thanks to ISRO’s remarkable 2025, that dream does not seem impossible anymore.&nbsp;

The year India touched the sky: How ISRO redefined our future in 2025

BlueBird Satellite: India’s ISRO Rockets BlueBird Block-2 Satellite for AST SpaceMobile

ISRO Launches LVM3 M6 with BlueBird Block-2 Satellite for AST SpaceMobile

ISRO undertakes its first commercial mission for a U.S. firm, marking a major milestone in India’s space journey. Touted as ISRO’s most powerful mission yet, the launch highlights India’s growing role in the global commercial space market.

ISRO's First Commercial Mission for US Firm | ISRO's Most Powerful Mission Yet

Indian Space Research Organisation (ISRO) has successfully launched the United States’ AST SpaceMobile’s BlueBird Block-2 communication satellite. It was launched at 8:55 AM today from the Second Launch Pad at Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh.


Breaking: Indian Space Agency's 5th and Final Rocket Launch of 2025

ISRO’s LVM3 rocket is set to attempt its heaviest launch ever, carrying the 6,100 kg BlueBird satellite built by US-based AST SpaceMobile. The mission aims to deliver space-based cellular broadband that can connect directly to smartphones, without ground towers.

This landmark launch positions ISRO at the center of a fast-growing, multi-billion-dollar space communications race dominated by players like SpaceX. With massive commercial and strategic stakes, the mission marks a defining moment for India’s rise as a trusted global launch partner and a major force in next-generation satellite technology.

American Satellite Trusts Indian Rocket for ISRO’s Most Powerful Mission Yet 

Indian space agency ISRO has commenced the 24-hour countdown to the Wednesday, (24th Dec) launch of US firm AST SpaceMobile's BlueBird-6 satellite aboard the LVM3 rocket. The three-stage LVM3 rocket, India's most capable spacefaring vehicle is to liftoff from the second launchpad of the Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh at 8:54am Indian Time, Wednesday. The satellite would be injected into orbit 520kms above the Earth, barely 16 minutes after launch.&nbsp;

<blockquote class="twitter-tweet" data-media-max-width="560">⏳ 24 hours to go! <a href="https://twitter.com/hashtag/LVM3M6?src=hash&amp;ref_src=twsrc%5Etfw">#LVM3M6</a> is set to launch the BlueBird Block-2 spacecraft tomorrow from SDSC SHAR. Final countdown begins. Stay tuned for live updates. Launch on 24 Dec 2025 at 08:54 IST. Youtube Livestreaming link:<a href="https://t.co/FMYCs31L3j">https://t.co/FMYCs31L3j</a> 🗓️ 24 Dec 2025 | 🕗 08:24 IST… <a href="https://t.co/tKoVu8rDUq">pic.twitter.com/tKoVu8rDUq</a>&mdash; ISRO (@isro) <a href="https://twitter.com/isro/status/2003306159927869784?ref_src=twsrc%5Etfw">December 23, 2025</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>

The countdown to a rocket launch involves sequential tasks like fueling, system checks, and approvals, synchronizing hundreds of people and automated systems. It's a crucial operational checklist during which all processes are validated.&nbsp;The 6,100kg BlueBird 6 satellite is the heaviest payload to be lifted by the LVM3 vehicle in its operational history. Therefore, this satellite would be the heaviest payload to be carried by an Indian rocket. LVM3 has a track record of having delivered success in all its eight missions to date.&nbsp;This mission is being executed as part of a commercial deal between ISRO's business arm NewSpace India Limited(NSIL) and the Texas-based AST SpaceMobile. As a launch services provider(rocket builder and operator), ISRO launches foreign-origin satellites to space on a commercial basis. Facilitated by NSIL, these commercial space missions are like a taxi ferrying a passenger. In this case, the passenger is the US firm, which pays the Indian Government for the launch service.&nbsp;This is the third commercial mission of LVM3, and the first time that the Indian LVM3 rocket is executing the mission for an American customer. Earlier, it had executed two launches for a European customer OneWeb(now Eutelsat OneWeb).<h2>About AST SpaceMobile and their internet-beaming satellites</h2>AST SpaceMobile is a Texas-based telecom company that aims to build and launch a fleet of satellites that can directly provide internet connectivity to mobile phones. Typically, only purpose-built satellite phones can facilitate satellite communication. These traditional satellite phone handsets are bulky and require visible antennas, they offer voice connectivity, and low-bandwidth texting and data services. Such services are offered by firms such as Iridium, Thuraya, among others. They are widely used in the defence and maritime sectors for providing connectivity where no communication infrastructure exists.&nbsp;Firms like AST and Starlink are attempting to change this by ensuring direct connectivity between smartphones and satellites. They intend to ensure that Android and Apple devices available in the market can communicate directly with satellites, without any modifications or special hardware. Thanks to the global coverage planned using a fleet of satellites, such services would eventually enable cell phone connectivity almost anywhere on Earth. In simple terms, one need not worry about being "not reachable" or "out of coverage area".&nbsp;As per reports, AST presently has a fleet of five first-generation (Block-1) satellites in orbit. The firm plans to launch a fleet of 45-60 second-generation (Block-2)satellites to offer services in major global regions, it is said.&nbsp;The firm has announced that they have a series of satellites that will be launching in the coming months. BlueBird 7 has shipped to the Cape Canaveral, Florida launch site this month, BlueBirds 8-16 are in various stages of production, with launches planned every 1-2 months on average during 2025 and 2026, the firm announced.&nbsp;They expect to have 45-60 satellites in orbit by year-end 2026. It is touted that these BlueBird satellites(by size) will be the largest commercial satellites ever deployed in Low Earth orbit (about 600kms above earth). Each of these satellites would carry a 2,400sq feet phased array antenna with true direct-to-cell broadband, with a claimed capability of up to 10,000 MHz of processing bandwidth and claimed peak speeds of 120 Mbps per cell.&nbsp;The firm says they have partnered with 50+ mobile network operators serving nearly 3 billion subscribers, "supported by a flexible spectrum strategy blending our own licensed spectrum with partner spectrum".&nbsp;While the launch of Bluebird-6 is being carried out from India, it must be noted that such direct-to-mobile satellite internet services have not been approved by the Indian Government. Firms like Starlink and Eutelsat OneWeb that are also into providing LEO satellite-based high-speed internet connectivity are in the process of seeking approvals from various departments of the Indian government. &nbsp;

ISRO has begun the countdown for launching AST SpaceMobile’s 6,100 kg BlueBird-6 satellite aboard its LVM3 rocket on Dec 24 from Sriharikota. This marks LVM3’s heaviest payload and first commercial mission for a US customer.

Indian space agency ISRO has commenced the 24-hour countdown to the Wednesday, (24th Dec) launch of US firm AST SpaceMobile's BlueBird-6 satellite aboard the LVM3 rocket. The three-stage LVM3 rocket, India's most capable spacefaring vehicle is to liftoff from the second launchpad of the Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh at 8:54am Indian Time, Wednesday. The satellite would be injected into orbit 520kms above the Earth, barely 16 minutes after launch.

ISRO has begun the countdown for launching AST SpaceMobile’s 6,100 kg BlueBird-6 satellite aboard its LVM3 rocket on Dec 24 from Sriharikota. This marks LVM3’s heaviest payload and first commercial mission for a US customer.

Countdown starts for ISRO's launch tomorrow

The Indian Space Research Organisation (ISRO) is preparing to launch US firm AST SpaceMobile's BlueBird-6 satellite on Wednesday (Dec 24) &nbsp;from the second launchpad of the Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh. The three-stage LVM3 rocket, the most capable space launch vehicle in India's fleet, is expected to liftoff at 8:54 am Indian time, carrying the 6,500kg BlueBird 6 to orbit(about 550 km above earth). This satellite would be the heaviest payload to be carried by an Indian rocket. LVM3 has a track record of delivering success in all its eight missions to date. &nbsp;&nbsp;This mission is being executed as part of a commercial deal between ISRO's business arm, NewSpace India Limited(NSIL,) and the Texas-based AST SpaceMobile. As a launch services provider(rocket builder and operator), ISRO launches foreign-origin satellites to space on a commercial basis. Facilitated by NSIL, these commercial space missions are like a taxi ferrying a passenger. In this case, the passenger is the US firm, which pays the Indian Government for the launch service. This is the third commercial mission of LVM3, and the first time that the Indian LVM3 rocket is executing the mission for an American customer. Earlier, it had executed two launches for a European customer, OneWeb(now Eutelsat OneWeb).<h2>About AST SpaceMobile and their internet-beaming satellites</h2>AST SpaceMobile is a Texas-based telecom company that aims to build and launch a fleet of satellites that can directly provide internet connectivity to mobile phones. Typically, only purpose-built satellite phones can facilitate satellite communication. These traditional satellite phone handsets are bulky and require visible antennas; they offer voice connectivity, and low-bandwidth texting and data services. Such services are offered by firms such as Iridium and Thuraya, among others. They are widely used in the defence and maritime sectors for providing connectivity where no communications infrastructure exists.&nbsp;Firms like AST and Starlink are attempting to change this by ensuring direct connectivity between smartphones and satellites. They intend to ensure that Android and Apple devices available in the market can communicate with the support of satellites, without any extra or special hardware. Thanks to the global coverage planned using a fleet of satellites, such services would eventually enable cell phone connectivity almost anywhere on Earth. In simple terms, one need not worry about being "not reachable" or "out of coverage area".&nbsp;As per reports, AST presently has a fleet of five first-generation (Block-1) satellites in orbit. The firm plans to launch a fleet of 45-60 second-generation (Block-2)satellites to offer services in major global regions, it is said.&nbsp;Also Read: <a href="https://www.wionews.com/world/lightning-strikes-world-tallest-burj-khalifa-dubai-crown-prince-shares-dramatic-visuals-watch-1766144146883">Lightning strikes world tallest Burj Khalifa, Dubai Crown Prince shares dramatic visuals - WATCH</a>&nbsp;The firm has announced that they have a series of satellites that will be launched in the coming months. BlueBird 7 has shipped to the Cape Canaveral, Florida launch site this month, BlueBirds 8-16 are in various stages of production, with launches planned every 1-2 months on average during 2025 and 2026, the firm announced. &nbsp;&nbsp;They expect to have 45-60 satellites in orbit by year-end 2026. It is touted that these BlueBird satellites(by size) will be the largest commercial satellites ever deployed in Low Earth orbit (about 600kms above Earth). Each of these satellites would carry a 2,400-foot phased array antenna with true direct-to-cell broadband, with a claimed capability of up to 10,000 MHz of processing bandwidth and claimed peak speeds of 120 Mbps per cell.&nbsp;The firm says they have partnered with 50+ mobile network operators serving nearly 3 billion subscribers, "supported by a flexible spectrum strategy blending our own licensed spectrum with partner spectrum".&nbsp; &nbsp;

AST SpaceMobile is a Texas-based telecom company that aims to build and launch a fleet of satellites that can directly provide internet connectivity to mobile phones.

The Indian Space Research Organisation (ISRO) is preparing to launch US firm AST SpaceMobile's BlueBird-6 satellite on Wednesday (Dec 24) from the second launchpad of the Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh. The three-stage LVM3 rocket, the most capable space launch vehicle in India's fleet, is expected to liftoff at 8:54 am Indian time, carrying the 6,500kg BlueBird 6 to orbit(about 550 km above earth). This satellite would be the heaviest payload to be carried by an Indian rocket. LVM3 has a track record of delivering success in all its eight missions to date. This mission is being executed as part of a commercial deal between ISRO's business arm, NewSpace India Limited(NSIL,) and the Texas-based AST SpaceMobile. As a launch services provider(rocket builder and operator), ISRO launches foreign-origin satellites to space on a commercial basis. Facilitated by NSIL, these commercial space missions are like a taxi ferrying a passenger. In this case, the passenger is the US firm, which pays the Indian Government for the launch service. This is the third commercial mission of LVM3, and the first time that the Indian LVM3 rocket is executing the mission for an American customer. Earlier, it had executed two launches for a European customer, OneWeb(now Eutelsat OneWeb). About AST SpaceMobile and their internet-beaming satellites AST SpaceMobile is a Texas-based telecom company that aims to build and launch a fleet of satellites that can directly provide internet connectivity to mobile phones. Typically, only purpose-built satellite phones can facilitate satellite communication. These traditional satellite phone handsets are bulky and require visible antennas; they offer voice connectivity, and low-bandwidth texting and data services. Such services are offered by firms such as Iridium and Thuraya, among others. They are widely used in the defence and maritime sectors for providing connectivity where no communications infrastructure exists. Firms like AST and Starlink are attempting to change this by ensuring direct connectivity between smartphones and satellites. They intend to ensure that Android and Apple devices available in the market can communicate with the support of satellites, without any extra or special hardware. Thanks to the global coverage planned using a fleet of satellites, such services would eventually enable cell phone connectivity almost anywhere on Earth. In simple terms, one need not worry about being "not reachable" or "out of coverage area". As per reports, AST presently has a fleet of five first-generation (Block-1) satellites in orbit. The firm plans to launch a fleet of 45-60 second-generation (Block-2)satellites to offer services in major global regions, it is said. Also Read: Lightning strikes world tallest Burj Khalifa, Dubai Crown Prince shares dramatic visuals - WATCH The firm has announced that they have a series of satellites that will be launched in the coming months. BlueBird 7 has shipped to the Cape Canaveral, Florida launch site this month, BlueBirds 8-16 are in various stages of production, with launches planned every 1-2 months on average during 2025 and 2026, the firm announced. They expect to have 45-60 satellites in orbit by year-end 2026. It is touted that these BlueBird satellites(by size) will be the largest commercial satellites ever deployed in Low Earth orbit (about 600kms above Earth). Each of these satellites would carry a 2,400-foot phased array antenna with true direct-to-cell broadband, with a claimed capability of up to 10,000 MHz of processing bandwidth and claimed peak speeds of 120 Mbps per cell. The firm says they have partnered with 50+ mobile network operators serving nearly 3 billion subscribers, "supported by a flexible spectrum strategy blending our own licensed spectrum with partner spectrum".

AST SpaceMobile is a Texas-based telecom company that aims to build and launch a fleet of satellites that can directly provide internet connectivity to mobile phones.

ISRO to launch US firm's Bluebird-6 satellite on December 24

India's space agency ISRO says that analysis of the Chandrayaan-3 lander data obtained from data from August 23, 2023 to September 03, 2023 shows first-of-its-kind of results on the plasma environment near the Moon’s surface at the Southern higher latitudes, revealing that the electrical environment near the Moon's surface at the South Polar Region is far more active than previously understood.


ISRO reveals electrified Moon environment

ISRO has revealed a groundbreaking discovery: the lunar south pole is electrically active, with Chandrayaan-3 detecting surprising electrical activity in the region. This electrified moon environment, previously unknown, suggests dynamic interactions between the lunar surface and solar radiation, potentially reshaping scientific understanding of the Moon’s geophysics. 

Moon Found Electrically Active: ISRO Reveals Electrified Environment 

Chandrayaan-3 discovers electrically active Moon, plasma storms at south pole

India-Russia space collaboration: The two countries have come together on several occasions for space missions. The Soviet Union has helped India with its technology to launch satellites and also send the first Indian into space.

India-Russia space collaboration: The two countries have come together on several occasions for space missions. The Soviet Union has helped India with its technology to launch satellites and also send the first Indian into space.

India-Russia space ties: Successful past missions, those in progress and one that did not work out

To enhance the lifting power of its spacefaring rockets, India is likely to purchase a limited number of Russian-origin Semi-cryogenic engines of the ‘RD-191’ variant, WION has learnt. If this deal goes ahead, this would mark the second time that India is purchasing spacefaring rocket engines from Russia. Back in the early 1990s, India purchased seven ‘KVD-1’ cryogenic engines from Russia. The ‘KVD-1’ engines were used in the upper stage of the early versions of India’s then heaviest rocket, GSLV.&nbsp;This latest deal for rocket engines is likely to take shape as Russian President Vladimir Putin visits India on Thursday, (4th Dec), for a two-day State visit hosted by Prime Minister Narendra Modi. Back in April 2023, this author had reported on such negotiations regarding the ‘RD-191’ engine having been underway and the possibility of manufacturing technology being transferred to India.&nbsp;Also Read: Exclusive: <a href="https://www.wionews.com/india-news/exclusive-india-russia-discuss-tech-transfer-making-of-rd-191-semi-cryo-rocket-engines-581784">India-Russia discuss tech transfer, making of 'RD-191' semi-cryo rocket engine</a>&nbsp;&nbsp;On Wednesday, (3rd Dec), a day ahead of President Putin’s visit, Russian space agency Roscosmos’ Director General Dmitry Bakanov said that Russia is preparing to announce “good news about space sector cooperation with India”. He elaborated that the areas of cooperation would include rocket engines, human spaceflight (astronaut missions), and collaboration on the development of national space stations. However, he did not offer specific information.&nbsp;&nbsp;In recent years, India-Russia space cooperation has been steadily growing. Four years ago, Russia provided astronaut training for India’s four ‘Gaganyaan’ astronaut candidates at Star City, near Moscow. When Indian astronauts undertake their space missions as part of Gaganyaan, they will be wearing the Russian Sokol KV2 suit manufactured by Zvezda, which the Indian candidates had familiarised themselves with during training in Russia.&nbsp;<h2>About the ‘RD-191’ rocket engine</h2>&nbsp;The ‘RD-191’ is a high-performance rocket engine fuelled by Kerosene and Liquid oxygen. It falls under the category semi-cryogenic, as its fuel rocket-grade Kerosene can be stored at room temperature; and the oxidizer liquid oxygen has to be stored at super-cooled cryogenic temperatures (below -150 degrees Centigrade). India’s existing rockets are powered by engines that burn: solid-fuel, liquid-fuel, and cryogenic fuel (where liquid hydrogen and liquid oxygen are stored at super-cooled temperatures). Though efforts have been underway to develop a semi-cryogenic engine dubbed ‘SE-2000’, India does not possess a flight-ready engine as of now.&nbsp;Developed by NPO Energomash, the ‘RD-191’ is a workhorse engine used in Russia’s Angara series of rockets. ‘RD-191’ is also a throttleable engine, which means that it can significantly reduce or increase its thrust mid-flight, a crucial capability that enables precise flight control, recovery, and reuse of rocket stages. While Russia itself does not possess reusable/vertical landing rockets, ‘RD-191’ offers some of the basic capabilities required in that regard.&nbsp;The RD-191 is approximately two-and-a-half times more powerful than ISRO’s workhorse Indo-French Vikas engine. While the Vikas engine delivers about 60-80 tonnes of thrust, the ‘RD-191’ is known to deliver between 200 and 220 tonnes of thrust. The Vikas engine is used in India’s PSLV, GSLV, and LVM3 rockets.&nbsp;<h2>Why does India need the ‘RD-191’?</h2>&nbsp;The Indian space agency ISRO’s largest and most powerful homegrown rocket LVM3 can lift only 4,000 kg to the Geosynchronous transfer orbit, which is a higher orbit into which communication satellites are launched. Likewise, the LVM3 is said to be capable of lifting around 8,000-10,000 kg to low earth orbit, which is about 500 km above the earth’s surface. India’s most powerful rocket LVM3 has a very modest lift capability when compared to its global peers operated by government-run space agencies or private firms.&nbsp;India’s rocketry muscle power deficiency has been evident on multiple occasions. In recent years, despite having its own rockets, India has had to pay foreign entities like Europe’s Arianegroup and America’s SpaceX to launch heavy satellites built in India. This was done because the satellites weighed much more than 4,000 kg, which is the maximum lifting capability of India’s LVM3 rocket.&nbsp;As India’s growing space ambitions include the Gaganyaan human spaceflight programme (astronaut mission), proposed Bharatiya Antariksh Station (Indian crewed space station), envisioned crewed moon landing, the country is in dire need of more rocketry muscle power. Designing and developing all-new rockets and rocket engines could take decades or longer, which is why India is looking to purchase the powerful ‘RD-191’ engine from Russia, WION has learnt.&nbsp;<h2>How would India utilise the ‘RD-191’ engines?</h2>&nbsp;While the Indian Space Research Organization (ISRO) wishes to design and develop powerful rockets for the future, India’s immediate priority is to enhance the lifting capability of the LVM3. To accomplish this, ISRO can use the Russian ‘RD-191’ engine and associated systems to replace the existing L110 or second stage of the three-stage LVM3 rocket. This is one step towards significantly enhancing the lifting power of the LVM3 rocket.&nbsp;&nbsp;Also, the LVM3’s lifting power can be further bolstered by using a more powerful C32 Cryogenic upper stage developed in-house by ISRO. This would help ISRO to launch satellites heavier than 4,000 kg from home soil on its own rocket, while reducing dependence on foreign rockets.&nbsp;&nbsp;In the foreseeable future, the LVM3 rocket powered by the Russian semi-cryogenic engine and the Indian C32 cryogenic engine could be used for various missions that were earlier not possible for ISRO due to the rocketry muscle power deficiency.&nbsp;ISRO’s future rockets can be designed and developed based on the capabilities offered by the ‘RD-191’ engine. In heavy-lift rocketry, multiple engines are used in a cluster to deliver high amounts of lifting power. Therefore, a single rocket would require a dozen or more engines. In such cases, production of the engine in India under licence would be a necessity. Which is why India and Russia have also been exploring the possibility of making the ‘RD-191’ in India, in partnership with homegrown industry, WION has learnt.

‘RD-191’ is a workhorse engine used in Russia’s Angara series of rockets. ‘RD-191’ is also a throttleable engine, which means that it can significantly reduce or increase its thrust mid-flight, a crucial capability that enables precise flight control, recovery, and reuse of rocket stages.

To enhance the lifting power of its spacefaring rockets, India is likely to purchase a limited number of Russian-origin Semi-cryogenic engines of the ‘RD-191’ variant, WION has learnt. If this deal goes ahead, this would mark the second time that India is purchasing spacefaring rocket engines from Russia. Back in the early 1990s, India purchased seven ‘KVD-1’ cryogenic engines from Russia. The ‘KVD-1’ engines were used in the upper stage of the early versions of India’s then heaviest rocket, GSLV. This latest deal for rocket engines is likely to take shape as Russian President Vladimir Putin visits India on Thursday, (4th Dec), for a two-day State visit hosted by Prime Minister Narendra Modi. Back in April 2023, this author had reported on such negotiations regarding the ‘RD-191’ engine having been underway and the possibility of manufacturing technology being transferred to India. Also Read: Exclusive: India-Russia discuss tech transfer, making of 'RD-191' semi-cryo rocket engine On Wednesday, (3rd Dec), a day ahead of President Putin’s visit, Russian space agency Roscosmos’ Director General Dmitry Bakanov said that Russia is preparing to announce “good news about space sector cooperation with India”. He elaborated that the areas of cooperation would include rocket engines, human spaceflight (astronaut missions), and collaboration on the development of national space stations. However, he did not offer specific information. In recent years, India-Russia space cooperation has been steadily growing. Four years ago, Russia provided astronaut training for India’s four ‘Gaganyaan’ astronaut candidates at Star City, near Moscow. When Indian astronauts undertake their space missions as part of Gaganyaan, they will be wearing the Russian Sokol KV2 suit manufactured by Zvezda, which the Indian candidates had familiarised themselves with during training in Russia. About the ‘RD-191’ rocket engine The ‘RD-191’ is a high-performance rocket engine fuelled by Kerosene and Liquid oxygen. It falls under the category semi-cryogenic, as its fuel rocket-grade Kerosene can be stored at room temperature; and the oxidizer liquid oxygen has to be stored at super-cooled cryogenic temperatures (below -150 degrees Centigrade). India’s existing rockets are powered by engines that burn: solid-fuel, liquid-fuel, and cryogenic fuel (where liquid hydrogen and liquid oxygen are stored at super-cooled temperatures). Though efforts have been underway to develop a semi-cryogenic engine dubbed ‘SE-2000’, India does not possess a flight-ready engine as of now. Developed by NPO Energomash, the ‘RD-191’ is a workhorse engine used in Russia’s Angara series of rockets. ‘RD-191’ is also a throttleable engine, which means that it can significantly reduce or increase its thrust mid-flight, a crucial capability that enables precise flight control, recovery, and reuse of rocket stages. While Russia itself does not possess reusable/vertical landing rockets, ‘RD-191’ offers some of the basic capabilities required in that regard. The RD-191 is approximately two-and-a-half times more powerful than ISRO’s workhorse Indo-French Vikas engine. While the Vikas engine delivers about 60-80 tonnes of thrust, the ‘RD-191’ is known to deliver between 200 and 220 tonnes of thrust. The Vikas engine is used in India’s PSLV, GSLV, and LVM3 rockets. Why does India need the ‘RD-191’? The Indian space agency ISRO’s largest and most powerful homegrown rocket LVM3 can lift only 4,000 kg to the Geosynchronous transfer orbit, which is a higher orbit into which communication satellites are launched. Likewise, the LVM3 is said to be capable of lifting around 8,000-10,000 kg to low earth orbit, which is about 500 km above the earth’s surface. India’s most powerful rocket LVM3 has a very modest lift capability when compared to its global peers operated by government-run space agencies or private firms. India’s rocketry muscle power deficiency has been evident on multiple occasions. In recent years, despite having its own rockets, India has had to pay foreign entities like Europe’s Arianegroup and America’s SpaceX to launch heavy satellites built in India. This was done because the satellites weighed much more than 4,000 kg, which is the maximum lifting capability of India’s LVM3 rocket. As India’s growing space ambitions include the Gaganyaan human spaceflight programme (astronaut mission), proposed Bharatiya Antariksh Station (Indian crewed space station), envisioned crewed moon landing, the country is in dire need of more rocketry muscle power. Designing and developing all-new rockets and rocket engines could take decades or longer, which is why India is looking to purchase the powerful ‘RD-191’ engine from Russia, WION has learnt. How would India utilise the ‘RD-191’ engines? While the Indian Space Research Organization (ISRO) wishes to design and develop powerful rockets for the future, India’s immediate priority is to enhance the lifting capability of the LVM3. To accomplish this, ISRO can use the Russian ‘RD-191’ engine and associated systems to replace the existing L110 or second stage of the three-stage LVM3 rocket. This is one step towards significantly enhancing the lifting power of the LVM3 rocket. Also, the LVM3’s lifting power can be further bolstered by using a more powerful C32 Cryogenic upper stage developed in-house by ISRO. This would help ISRO to launch satellites heavier than 4,000 kg from home soil on its own rocket, while reducing dependence on foreign rockets. In the foreseeable future, the LVM3 rocket powered by the Russian semi-cryogenic engine and the Indian C32 cryogenic engine could be used for various missions that were earlier not possible for ISRO due to the rocketry muscle power deficiency. ISRO’s future rockets can be designed and developed based on the capabilities offered by the ‘RD-191’ engine. In heavy-lift rocketry, multiple engines are used in a cluster to deliver high amounts of lifting power. Therefore, a single rocket would require a dozen or more engines. In such cases, production of the engine in India under licence would be a necessity. Which is why India and Russia have also been exploring the possibility of making the ‘RD-191’ in India, in partnership with homegrown industry, WION has learnt.

‘RD-191’ is a workhorse engine used in Russia’s Angara series of rockets. ‘RD-191’ is also a throttleable engine, which means that it can significantly reduce or increase its thrust mid-flight, a crucial capability that enables precise flight control, recovery, and reuse of rocket stages.

Exclusive: India to buy Russia’s ‘RD-191’ semi-cryo rocket engines?

Indian Space Research Organisation (ISRO) achieved several new milestones in the year 2025. The successful docking of two SPADEX satellites, the 100th mission for ISRO, and having the first Indian at the ISS are among the few that had the Indian flag flying high in 2025. 

Indian Space Research Organisation (ISRO) achieved several new milestones in the year 2025. The successful docking of two SpaDeX satellites, the space agency's 100th mission, and having the first Indian at the ISS are among the few that had the Indian flag flying high in 2025.&nbsp;

YEARENDER: 7 Indian space achievements of 2025 — SpaDeX, an Indian at ISS, 100th mission

While ISRO has operated three variants of Cryogenic rocket engines(one foreign-origin and two indigenously developed) and associated stages for more than two decades, in a first, ISRO restarted its indigenous C25 Cryogenic stage during the LVM3M5/CMOS-03 mission earlier this month.&nbsp;A cryogenic rocket engine is among the most efficient means of propelling a space vehicle. It is also among the most sophisticated technologies to master. A cryogenic engine, its fuel tanks, and all associated systems working together form a Cryogenic stage.&nbsp;After the primary mission was successfully accomplished, ISRO announced the achievement of the Cryogenic stage reignition. "After the CMS-03 satellite was injected into the designated orbit, the C25 Cryogenic upper stage was reoriented, and after 100 seconds of waiting time, the Cryogenic upper stage was reignited. This is the first time that the Cryogenic upper stage is being reignited in the deep vacuum of space," said ISRO.&nbsp;Why is a Cryogenic stage restart&nbsp; technologically challenging?&nbsp;A Cryognic engine burns Liquid hydrogen (stored at -253 degrees Celsius) and Liquid oxygen (stored at -183 degrees Celsius). The handling and storage of these fuels is highly challenging because they need to be super cooled to ensure that the gases exist in liquid form.&nbsp;On Earth, the fuels can be maintained in a super cooled condition. In tanks on Earth, gravity pulls the fuel downwards and keeps it grounded within the tank.In the microgravity environment of space, fuel floats inside the rocket's fuel tank, which could cause bubbles and vapour pockets. To restart the engine, the turbopumps require a continuous liquid fuel feed, not gas or bubbles.&nbsp;&nbsp;First, the fuel must be settled at the bottom of the tank. For that, special motors known as ullaging motors/settling thrusters need to be used to push the fuel to the bottom of the tank. If this process is not done correctly, the pump could fail when it takes in gas, instead of fuel.&nbsp;&nbsp;In earth orbit, temperatures range from 150 degrees Celsius to -150 degrees Celsius, therefore the fuel tank must be insulated and thermally maintained in the ideal condition. Heat from sunlight could causes liquid hydrogen to boil and lead to formation of gas bubbles and change in pressure. "Once the Cryogenic engine is fired once and then it is shutdown, we will again have to re-attain the required thermal conditions for a reignition. Engine components like injectors and turbopumps needs to be pre-chilled to ideal temperature again before reignition. Adequate quantity of fuel needs to be there in the tank for reignition, the fuel must be at the ideal temperature and pressure," ISRO Chief Dr. V. Narayanan explained to WION.&nbsp;&nbsp;In addition to all these factors, the ignitor must work reliably in vacuum and near-zero pressure of space. For this mission, ISRO placed three ignitors for the restart of the engine, said the Chief.&nbsp;ISRO has the capability to restart the 4th or final stage of the PSLV rocket multiple times, because PSLV uses Unsymmetric Dimethyl Hydrazine(UDMH) + N204 fuel combination, which can ignite on coming with contact with each other. These are known as hypergolic fuels. Therefore, just opening the two valves and bringing the fuel and oxidizer into contact can enable the engine firing. In contrast, a cryogenic engine re-firing is much more complicated and requires many factors to work together perfectly.&nbsp;In 2022 and 2023, ISRO managed to launch a total of 72 OneWeb satellites in two launches. While ISRO did not have Cryogenic engine restart capability at that time, ISRO used cold gas thrusters, where an inert gas like nitrogen or helium is pushed out of a compressed tank. This is like letting air out of a balloon, which leads to the balloon moving in the opposite direction of the gas exit.&nbsp;That's how ISRO steered the upper stage and aligned it perfectly to eject 36 satellites in a single mission. However, cold gas thrusters offer very minimal thrust, and are useful only for minor alignment changes and not for completely changing the orbit.&nbsp;&nbsp;<h2>What additional capability does a Cryo stage re-ignition offer?</h2> ISRO Chief Dr. V. Narayanan said that the re-ignition of the Cryogenic upper stage in the vacuum of space enables multi-orbit missions where a single LVM3 rocket can carry satellites to different orbits. In simple terms, it is a like a vehicle performing multiple start-stops to allow passengers to get down at different locations.&nbsp;Further, the reignition of&nbsp;the Cryogenic stage can also be used for post-mission disposal or de-orbiting of the stage. This is a step that is undertaken to remove the used rocket stage from orbit, so that it does not end up as space debris. This is done to ensure space sustainability, and minimize the overcrowding of orbits.&nbsp;Dr. Narayanan suggested that ISRO would conduct more such cryogenic engine reignition tests in space, and study the data thoroughly before attempting multi-orbit missions using the LVM3 rocket's C25 cryogenic stage reignition. He said that ISRO needed to perform more such tests when future LVM3 launch missions provide such opportunities.

ISRO successfully restarted its C25 cryogenic stage in space for the first time during the LVM3-M5/CMS-03 mission. The complex restart enables multi-orbit missions and better disposal of rocket stages. ISRO will conduct more tests to refine this crucial capability.

While ISRO has operated three variants of Cryogenic rocket engines(one foreign-origin and two indigenously developed) and associated stages for more than two decades, in a first, ISRO restarted its indigenous C25 Cryogenic stage during the LVM3M5/CMOS-03 mission earlier this month. A cryogenic rocket engine is among the most efficient means of propelling a space vehicle. It is also among the most sophisticated technologies to master. A cryogenic engine, its fuel tanks, and all associated systems working together form a Cryogenic stage. After the primary mission was successfully accomplished, ISRO announced the achievement of the Cryogenic stage reignition. "After the CMS-03 satellite was injected into the designated orbit, the C25 Cryogenic upper stage was reoriented, and after 100 seconds of waiting time, the Cryogenic upper stage was reignited. This is the first time that the Cryogenic upper stage is being reignited in the deep vacuum of space," said ISRO. Why is a Cryogenic stage restart technologically challenging? A Cryognic engine burns Liquid hydrogen (stored at -253 degrees Celsius) and Liquid oxygen (stored at -183 degrees Celsius). The handling and storage of these fuels is highly challenging because they need to be super cooled to ensure that the gases exist in liquid form. On Earth, the fuels can be maintained in a super cooled condition. In tanks on Earth, gravity pulls the fuel downwards and keeps it grounded within the tank. In the microgravity environment of space, fuel floats inside the rocket's fuel tank, which could cause bubbles and vapour pockets. To restart the engine, the turbopumps require a continuous liquid fuel feed, not gas or bubbles. First, the fuel must be settled at the bottom of the tank. For that, special motors known as ullaging motors/settling thrusters need to be used to push the fuel to the bottom of the tank. If this process is not done correctly, the pump could fail when it takes in gas, instead of fuel. In earth orbit, temperatures range from 150 degrees Celsius to -150 degrees Celsius, therefore the fuel tank must be insulated and thermally maintained in the ideal condition. Heat from sunlight could causes liquid hydrogen to boil and lead to formation of gas bubbles and change in pressure. "Once the Cryogenic engine is fired once and then it is shutdown, we will again have to re-attain the required thermal conditions for a reignition. Engine components like injectors and turbopumps needs to be pre-chilled to ideal temperature again before reignition. Adequate quantity of fuel needs to be there in the tank for reignition, the fuel must be at the ideal temperature and pressure," ISRO Chief Dr. V. Narayanan explained to WION. In addition to all these factors, the ignitor must work reliably in vacuum and near-zero pressure of space. For this mission, ISRO placed three ignitors for the restart of the engine, said the Chief. ISRO has the capability to restart the 4th or final stage of the PSLV rocket multiple times, because PSLV uses Unsymmetric Dimethyl Hydrazine(UDMH) + N204 fuel combination, which can ignite on coming with contact with each other. These are known as hypergolic fuels. Therefore, just opening the two valves and bringing the fuel and oxidizer into contact can enable the engine firing. In contrast, a cryogenic engine re-firing is much more complicated and requires many factors to work together perfectly. In 2022 and 2023, ISRO managed to launch a total of 72 OneWeb satellites in two launches. While ISRO did not have Cryogenic engine restart capability at that time, ISRO used cold gas thrusters, where an inert gas like nitrogen or helium is pushed out of a compressed tank. This is like letting air out of a balloon, which leads to the balloon moving in the opposite direction of the gas exit. That's how ISRO steered the upper stage and aligned it perfectly to eject 36 satellites in a single mission. However, cold gas thrusters offer very minimal thrust, and are useful only for minor alignment changes and not for completely changing the orbit. What additional capability does a Cryo stage re-ignition offer? ISRO Chief Dr. V. Narayanan said that the re-ignition of the Cryogenic upper stage in the vacuum of space enables multi-orbit missions where a single LVM3 rocket can carry satellites to different orbits. In simple terms, it is a like a vehicle performing multiple start-stops to allow passengers to get down at different locations. Further, the reignition of the Cryogenic stage can also be used for post-mission disposal or de-orbiting of the stage. This is a step that is undertaken to remove the used rocket stage from orbit, so that it does not end up as space debris. This is done to ensure space sustainability, and minimize the overcrowding of orbits. Dr. Narayanan suggested that ISRO would conduct more such cryogenic engine reignition tests in space, and study the data thoroughly before attempting multi-orbit missions using the LVM3 rocket's C25 cryogenic stage reignition. He said that ISRO needed to perform more such tests when future LVM3 launch missions provide such opportunities.

ISRO successfully restarted its C25 cryogenic stage in space for the first time during the LVM3-M5/CMS-03 mission. The complex restart enables multi-orbit missions and better disposal of rocket stages. ISRO will conduct more tests to refine this crucial capability.

Explained: ISRO's maiden Cryogenic stage restart in space

A groundbreaking ISRO study reveals strong evidence of water ice hidden beneath the Moon’s polar craters. Using Chandrayaan mission data, scientists found sub-surface ice levels up to eight times higher than surface deposits — a major step toward understanding lunar resources. The discovery could redefine future Moon missions, from habitation plans to fuel generation.

ISRO Finds Evidence of Water Ice Beneath Moon’s Polar Craters

ISRO: India has successfully launched its heaviest-ever communication satellite, CMS-03, using the LVM3 ‘Bahubali’ rocket from the Sriharikota spaceport. Weighing approximately 4,410 kilograms, the satellite is set to bolster the Indian Navy’s network capabilities and enhance communication across defense platforms. This milestone launch demonstrates ISRO’s growing expertise in deploying large payloads into geostationary orbit and strengthens India’s strategic capabilities in space technology. 

ISRO: India Shoots Off Heaviest Satellite with ISRO’s ‘Bahubali’ Rocket 

ISRO’s heaviest satellite launch to date lifted off on Sunday, as CMS-03 mission, weighing approximately 4,410 kg began its journey to space. The satellite was launched aboard the LVM3-M5 ‘Bahubali’ rocket from Sriharikota, marking the first time Isro sent a satellite exceeding 4,000 kg into geosynchronous transfer orbit entirely from Indian soil.


Prime Minister Narendra Modi hails ISRO's CMS-03 success 

India's 'Bahubali' rocket lifts off heaviest comsat from home soil

Isro’s heaviest satellite launch to date lifted off on Sunday, as CMS-03 mission, weighing approximately 4,410 kg began its journey to space. The satellite was launched aboard the LVM3-M5 ‘Bahubali’ rocket from Sriharikota, marking the first time Isro sent a satellite exceeding 4,000 kg into geosynchronous transfer orbit entirely from Indian soil.


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The satellite will be lofted aboard the LVM3, India's most powerful launch vehicle, which has previously delivered milestone missions like Chandrayaan-3 to the Moon.​


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GSAT-7R or CMS-03, India's largest military communications satellite, will enable secure and real-time data, video, and voice connectivity between Indian Navy ships, submarines, aircraft, and Maritime Operations Centres, the Navy said. This indigenously built satellite is to be launched by India's largest rocket LVM3 from ISRO's Satish Dhawan Space Centre at Sriharikota, Andhra Pradesh, at 5:26 pm Sunday (2nd Nov).The 4,400 kg GSAT-7R is India's heaviest military communication satellite and the heaviest satellite that will be launched from home soil. According to the Indian Navy, the satellite carries components that were specifically developed to meet its operational requirements. The satellite is meant to provide telecommunications coverage across the Indian Ocean region and enhance the Navy's space-based communications and maritime domain awareness capabilities.After liftoff at 5:26 pm on Sunday, the three-stage rocket is expected to complete the mission in about 16 minutes. The satellite will be hurled into a lower initial orbit and then gradually raised into the destined orbit over the next few weeks.Eventually, all heavy communication satellites are placed in geostationary orbit, which is about 36,000 km above the Earth's equator. From there, the satellite will be able to provide coverage for about one-third of the Earth. In this case, the CMS-03 will be placed above India, so that it can provide coverage in the vast maritime region surrounding India.The CMS-03/GSAT-7R is a replacement for the ageing GSAT-7 that ISRO built for the Indian Navy in 2013. The 2,650 kg GSAT-7 was launched from overseas aboard Europe's Ariane rocket in August 2013, as ISRO did not possess the capability to lift such a heavy satellite at the time. Therefore, ISRO paid the European firm to ferry the Indian satellite to space.&nbsp; &nbsp;

India will launch GSAT-7R (CMS-03), its largest military communication satellite, aboard the LVM3 rocket from Sriharikota at 5:26 pm on Sunday (Nov 2). Weighing 4,400 kg, the indigenously built satellite will boost secure naval communication and replace the ageing GSAT-7 launched in 2013.


GSAT-7R or CMS-03, India's largest military communications satellite, will enable secure and real-time data, video, and voice connectivity between Indian Navy ships, submarines, aircraft, and Maritime Operations Centres, the Navy said. This indigenously built satellite is to be launched by India's largest rocket LVM3 from ISRO's Satish Dhawan Space Centre at Sriharikota, Andhra Pradesh, at 5:26 pm Sunday (2nd Nov). The 4,400 kg GSAT-7R is India's heaviest military communication satellite and the heaviest satellite that will be launched from home soil. According to the Indian Navy, the satellite carries components that were specifically developed to meet its operational requirements. The satellite is meant to provide telecommunications coverage across the Indian Ocean region and enhance the Navy's space-based communications and maritime domain awareness capabilities. After liftoff at 5:26 pm on Sunday, the three-stage rocket is expected to complete the mission in about 16 minutes. The satellite will be hurled into a lower initial orbit and then gradually raised into the destined orbit over the next few weeks. Eventually, all heavy communication satellites are placed in geostationary orbit, which is about 36,000 km above the Earth's equator. From there, the satellite will be able to provide coverage for about one-third of the Earth. In this case, the CMS-03 will be placed above India, so that it can provide coverage in the vast maritime region surrounding India. The CMS-03/GSAT-7R is a replacement for the ageing GSAT-7 that ISRO built for the Indian Navy in 2013. The 2,650 kg GSAT-7 was launched from overseas aboard Europe's Ariane rocket in August 2013, as ISRO did not possess the capability to lift such a heavy satellite at the time. Therefore, ISRO paid the European firm to ferry the Indian satellite to space.

India will launch GSAT-7R (CMS-03), its largest military communication satellite, aboard the LVM3 rocket from Sriharikota at 5:26 pm on Sunday (Nov 2). Weighing 4,400 kg, the indigenously built satellite will boost secure naval communication and replace the ageing GSAT-7 launched in 2013.

ISRO's GSAT-7R will enable real-time data and video link for Indian Navy's ships, aircraft

ISRO is all set for its fourth rocket launch of the year, deploying the CMS-03 (GSAT-7R) satellite for the Indian Navy. The 4,400kg communication satellite — the heaviest ever launched from Indian soil — will enhance naval connectivity and coordination. The LVM3 rocket, with a flawless track record, will complete the mission in just 16 minutes.


ISRO develops indigenous satellite to bolster naval communications

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